Since the decrementer and timekeeping code was moved over to using
the generic clockevents and timekeeping infrastructure, several
variables and functions have been obsolete and effectively unused.
This deletes them.
In particular, wakeup_decrementer() is no longer needed since the
generic code reprograms the decrementer as part of the process of
resuming the timekeeping code, which happens during sysdev resume.
Thus the wakeup_decrementer calls in the suspend_enter methods for
52xx platforms have been removed. The call in the powermac cpu
frequency change code has been replaced by set_dec(1), which will
cause a timer interrupt as soon as interrupts are enabled, and the
generic code will then reprogram the decrementer with the correct
value.
This also simplifies the generic_suspend_en/disable_irqs functions
and makes them static since they are not referenced outside time.c.
The preempt_enable/disable calls are removed because the generic
code has disabled all but the boot cpu at the point where these
functions are called, so we can't be moved to another cpu.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Currently it is possible for userspace to see the result of
gettimeofday() going backwards by 1 microsecond, assuming that
userspace is using the gettimeofday() in the VDSO. The VDSO
gettimeofday() algorithm computes the time in "xsecs", which are
units of 2^-20 seconds, or approximately 0.954 microseconds,
using the algorithm
now = (timebase - tb_orig_stamp) * tb_to_xs + stamp_xsec
and then converts the time in xsecs to seconds and microseconds.
The kernel updates the tb_orig_stamp and stamp_xsec values every
tick in update_vsyscall(). If the length of the tick is not an
integer number of xsecs, then some precision is lost in converting
the current time to xsecs. For example, with CONFIG_HZ=1000, the
tick is 1ms long, which is 1048.576 xsecs. That means that
stamp_xsec will advance by either 1048 or 1049 on each tick.
With the right conditions, it is possible for userspace to get
(timebase - tb_orig_stamp) * tb_to_xs being 1049 if the kernel is
slightly late in updating the vdso_datapage, and then for stamp_xsec
to advance by 1048 when the kernel does update it, and for userspace
to then see (timebase - tb_orig_stamp) * tb_to_xs being zero due to
integer truncation. The result is that time appears to go backwards
by 1 microsecond.
To fix this we change the VDSO gettimeofday to use a new field in the
VDSO datapage which stores the nanoseconds part of the time as a
fractional number of seconds in a 0.32 binary fraction format.
(Or put another way, as a 32-bit number in units of 0.23283 ns.)
This is convenient because we can use the mulhwu instruction to
convert it to either microseconds or nanoseconds.
Since it turns out that computing the time of day using this new field
is simpler than either using stamp_xsec (as gettimeofday does) or
stamp_xtime.tv_nsec (as clock_gettime does), this converts both
gettimeofday and clock_gettime to use the new field. The existing
__do_get_tspec function is converted to use the new field and take
a parameter in r7 that indicates the desired resolution, 1,000,000
for microseconds or 1,000,000,000 for nanoseconds. The __do_get_xsec
function is then unused and is deleted.
The new algorithm is
now = ((timebase - tb_orig_stamp) << 12) * tb_to_xs
+ (stamp_xtime_seconds << 32) + stamp_sec_fraction
with 'now' in units of 2^-32 seconds. That is then converted to
seconds and either microseconds or nanoseconds with
seconds = now >> 32
partseconds = ((now & 0xffffffff) * resolution) >> 32
The 32-bit VDSO code also makes a further simplification: it ignores
the bottom 32 bits of the tb_to_xs value, which is a 0.64 format binary
fraction. Doing so gets rid of 4 multiply instructions. Assuming
a timebase frequency of 1GHz or less and an update interval of no
more than 10ms, the upper 32 bits of tb_to_xs will be at least
4503599, so the error from ignoring the low 32 bits will be at most
2.2ns, which is more than an order of magnitude less than the time
taken to do gettimeofday or clock_gettime on our fastest processors,
so there is no possibility of seeing inconsistent values due to this.
This also moves update_gtod() down next to its only caller, and makes
update_vsyscall use the time passed in via the wall_time argument rather
than accessing xtime directly. At present, wall_time always points to
xtime, but that could change in future.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
crash_kexec_wait_realmode() is defined only if CONFIG_PPC_STD_MMU_64
and CONFIG_SMP, but is called if CONFIG_PPC_STD_MMU_64 even if !CONFIG_SMP.
Fix the conditional compilation around the invocation.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When SPARSE_IRQ is set, irq_to_desc() can
return NULL. While the code here has a
check for NULL, it's not really correct.
Fix it by separating the check for it.
This fixes CPU hot unplug for me.
Reported-by: Alastair Bridgewater <alastair.bridgewater@gmail.com>
Cc: stable@kernel.org [2.6.32+]
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
If we configure with CONFIG_SMP=n or set NR_CPUS less than the number of
SMT threads we will set the max cores property to 0 in the
ibm,client-architecture-support structure. On new versions of firmware that
understand this property it obliges and terminates our partition.
Use DIV_ROUND_UP so we handle not only the CONFIG_SMP=n case but also the
case where NR_CPUS isn't a multiple of the number of SMT threads.
Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Just whitelist these extra compiler generated symbols.
Fixes these errors:
Error: External symbol '_restgpr0_14' referenced from prom_init.c
Error: External symbol '_restgpr0_20' referenced from prom_init.c
Error: External symbol '_restgpr0_22' referenced from prom_init.c
Error: External symbol '_restgpr0_24' referenced from prom_init.c
Error: External symbol '_restgpr0_25' referenced from prom_init.c
Error: External symbol '_restgpr0_26' referenced from prom_init.c
Error: External symbol '_restgpr0_27' referenced from prom_init.c
Error: External symbol '_restgpr0_28' referenced from prom_init.c
Error: External symbol '_restgpr0_29' referenced from prom_init.c
Error: External symbol '_restgpr0_31' referenced from prom_init.c
Error: External symbol '_savegpr0_14' referenced from prom_init.c
Error: External symbol '_savegpr0_20' referenced from prom_init.c
Error: External symbol '_savegpr0_22' referenced from prom_init.c
Error: External symbol '_savegpr0_24' referenced from prom_init.c
Error: External symbol '_savegpr0_25' referenced from prom_init.c
Error: External symbol '_savegpr0_26' referenced from prom_init.c
Error: External symbol '_savegpr0_27' referenced from prom_init.c
Error: External symbol '_savegpr0_28' referenced from prom_init.c
Error: External symbol '_savegpr0_29' referenced from prom_init.c
Error: External symbol '_savegpr0_31' referenced from prom_init.c
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When power_pmu_disable() removes the given event from a particular index into
cpuhw->event[], it shuffles down higher event[] entries. But, this array is
paired with cpuhw->events[] and cpuhw->flags[] so should shuffle them
similarly.
If these arrays get out of sync, code such as power_check_constraints() will
fail. This caused a bug where events were temporarily disabled and then failed
to be re-enabled; subsequent code tried to write_pmc() with its (disabled) idx
of 0, causing a message "oops trying to write PMC0". This triggers this bug on
POWER7, running a miss-heavy test:
perf record -e L1-dcache-load-misses -e L1-dcache-store-misses ./misstest
Signed-off-by: Matt Evans <matt@ozlabs.org>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
At present, hw_breakpoint_slots() returns 1 regardless of what
type of breakpoint is specified in the type argument. Since we
don't define CONFIG_HAVE_MIXED_BREAKPOINTS_REGS, there are
separate values for TYPE_INST and TYPE_DATA, and hw_breakpoint_slots()
returns 1 for both, effectively advertising instruction breakpoint
support which doesn't exist.
This fixes it by making hw_breakpoint_slots return 1 for TYPE_DATA
and 0 for TYPE_INST. This moves hw_breakpoint_slots() from the
powerpc hw_breakpoint.h to hw_breakpoint.c because the definitions
of TYPE_INST and TYPE_DATA aren't available in <asm/hw_breakpoint.h>.
They are defined in <linux/hw_breakpoint.h> but we can't include
that header in <asm/hw_breakpoint.h>, and nor can we rely on
<linux/hw_breakpoint.h> being included before <asm/hw_breakpoint.h>.
Since hw_breakpoint_slots() is only called at boot time, there is
no performance impact from making it a real function rather than
a static inline.
Signed-off-by: Paul Mackerras <paulus@samba.org>
The code we had to clear the MSR_SE bit was not doing anything because
the caller (ultimately single_step_exception() in traps.c) had already
cleared. Instead of trying to leave MSR_SE set if the TIF_SINGLESTEP
flag is set (which indicates that the process is being single-stepped
by ptrace), we instead return NOTIFY_DONE in that case, which means
the caller will generate a SIGTRAP for the process.
Signed-off-by: Paul Mackerras <paulus@samba.org>
The code would accept an access to an address one byte past the end
of the requested range as legitimate, due to having a "<=" rather than
a "<". This fixes that and cleans up the code a bit.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Many a times, the requested breakpoint length can be less than the
fixed breakpoint length i.e. 8 bytes supported by PowerPC 64-bit
server (Book III S) processors. This could lead to extraneous
interrupts resulting in false breakpoint notifications. This
detects and discards such interrupts for non-ptrace requests.
We don't change ptrace behaviour to avoid breaking compatability.
[Suggestion from Paul Mackerras <paulus@samba.org> to add a new flag in
'struct arch_hw_breakpoint' to identify extraneous interrupts]
Signed-off-by: K.Prasad <prasad@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
A signal delivered between a hw_breakpoint_handler() and the
single_step_dabr_instruction() will not have the breakpoint active
while the signal handler is running -- the signal delivery will
set up a new MSR value which will not have MSR_SE set, so we
won't get the signal step interrupt until and unless the signal
handler returns (which it may never do).
To fix this, we restore the breakpoint when delivering a signal --
we clear the MSR_SE bit and set the DABR again. If the signal
handler returns, the DABR interrupt will occur again when the
instruction that we were originally trying to single-step gets
re-executed.
[Paul Mackerras <paulus@samba.org> pointed out the need to do this.]
Signed-off-by: K.Prasad <prasad@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
If an alignment interrupt occurs on an instruction that is being
single-stepped, the alignment interrupt handler currently handles
the single-step condition by unconditionally sending a SIGTRAP to
the process. Other synchronous interrupts that result in the
instruction being emulated do likewise.
With hw_breakpoint support, the hw_breakpoint code needs to be able
to intercept these single-step events as well as those where the
instruction executes normally and a trace interrupt happens.
Fix this by making emulate_single_step() use the existing
single_step_exception() function instead of calling _exception()
directly. We then make single_step_exception() use the abstracted
clear_single_step() rather than clearing bits in the MSR image
directly so that emulate_single_step() will continue to work
correctly on Book 3E processors.
Signed-off-by: K.Prasad <prasad@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Implement perf-events based hw-breakpoint interfaces for PowerPC
64-bit server (Book III S) processors. This allows access to a
given location to be used as an event that can be counted or
profiled by the perf_events subsystem.
This is done using the DABR (data breakpoint register), which can
also be used for process debugging via ptrace. When perf_event
hw_breakpoint support is configured in, the perf_event subsystem
manages the DABR and arbitrates access to it, and ptrace then
creates a perf_event when it is requested to set a data breakpoint.
[Adopted suggestions from Paul Mackerras <paulus@samba.org> to
- emulate_step() all system-wide breakpoints and single-step only the
per-task breakpoints
- perform arch-specific cleanup before unregistration through
arch_unregister_hw_breakpoint()
]
Signed-off-by: K.Prasad <prasad@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
When trying to flash a machine via the update_flash command, Anton received the
following error:
Restarting system.
FLASH: kernel bug...flash list header addr above 4GB
The code in question has a comment that the flash list should be in
the kernel data and therefore under 4GB:
/* NOTE: the "first" block list is a global var with no data
* blocks in the kernel data segment. We do this because
* we want to ensure this block_list addr is under 4GB.
*/
Unfortunately the Kconfig option is marked tristate which means the variable
may not be in the kernel data and could be above 4GB.
Instead of relying on the data segment being below 4GB, use the static
data buffer allocated by the kernel for use by rtas. Since we don't
use the header struct directly anymore, convert it to a simple pointer.
Reported-By: Anton Blanchard <anton@samba.org>
Signed-Off-By: Milton Miller <miltonm@bga.com
Tested-By: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Irq stacks provide an essential protection from stack overflows through
external interrupts, at the cost of two additionals stacks per CPU.
Enable them unconditionally to simplify the kernel build and prevent
people from accidentally disabling them.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
kexec_perpare_cpus_wait() iterates i through NR_CPUS to check
paca[i].kexec_state of each to make sure they have quiesced.
However now we have dynamic PACA allocation, paca[NR_CPUS] is not necessarily
valid and we overrun the array; spurious "cpu is not possible, ignoring"
errors result. This patch iterates for_each_online_cpu so stays
within the bounds of paca[] -- and every CPU is now 'possible'.
Signed-off-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
PCI: clear bridge resource range if BIOS assigned bad one
PCI: hotplug/cpqphp, fix NULL dereference
Revert "PCI: create function symlinks in /sys/bus/pci/slots/N/"
PCI: change resource collision messages from KERN_ERR to KERN_INFO
Yannick found that video does not work with 2.6.34. The cause of this
bug was that the BIOS had assigned the wrong range to the PCI bridge
above the video device. Before 2.6.34 the kernel would have shrunk
the size of the bridge window, but since
d65245c PCI: don't shrink bridge resources
the kernel will avoid shrinking BIOS ranges.
So zero out the old range if we fail to claim it at boot time; this will
cause us to allocate a new range at startup, restoring the 2.6.34
behavior.
Fixes regression https://bugzilla.kernel.org/show_bug.cgi?id=16009.
Reported-by: Yannick <yannick.roehlly@free.fr>
Acked-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
emulate_step() in kprobe_handler() would've already determined if the
probed instruction can be emulated. We single-step in hardware only if
the instruction couldn't be emulated. resume_execution() therefore is
superfluous -- all we need is to fix up the instruction pointer after
single-stepping.
Thanks to Paul Mackerras for catching this.
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
powerpc: Don't export cvt_fd & _df when CONFIG_PPC_FPU is not set
powerpc/44x: icon: select SM502 and frame buffer console support
powerpc/85xx: Add P1021MDS board support
powerpc/85xx: Change MPC8572DS camp dtses for MSI sharing
powerpc/fsl_msi: add removal path and probe failing path
powerpc/fsl_msi: enable msi sharing through AMP OSes
powerpc/fsl_msi: enable msi allocation in all banks
powerpc/fsl_msi: fix the conflict of virt_msir's chip_data
powerpc/fsl_msi: Add multiple MSI bank support
powerpc/kexec: Add support for FSL-BookE
powerpc/fsl-booke: Move the entry setup code into a seperate file
powerpc/fsl-booke: fix the case where we are not in the first page
powerpc/85xx: Enable support for ports 3 and 4 on 8548 CDS
powerpc/fsl-booke: Add hibernation support for FSL BookE processors
powerpc/e500mc: Implement machine check handler.
powerpc/44x: Add basic ICON PPC440SPe board support
powerpc/44x: Fix UART clocks on 440SPe
powerpc/44x: Add reset-type to katmai.dts
powerpc/44x: Adding PCI-E support for PowerPC 460SX based SOC.
* 'for-35' of git://repo.or.cz/linux-kbuild: (81 commits)
kbuild: Revert part of e8d400a to resolve a conflict
kbuild: Fix checking of scm-identifier variable
gconfig: add support to show hidden options that have prompts
menuconfig: add support to show hidden options which have prompts
gconfig: remove show_debug option
gconfig: remove dbg_print_ptype() and dbg_print_stype()
kconfig: fix zconfdump()
kconfig: some small fixes
add random binaries to .gitignore
kbuild: Include gen_initramfs_list.sh and the file list in the .d file
kconfig: recalc symbol value before showing search results
.gitignore: ignore *.lzo files
headerdep: perlcritic warning
scripts/Makefile.lib: Align the output of LZO
kbuild: Generate modules.builtin in make modules_install
Revert "kbuild: specify absolute paths for cscope"
kbuild: Do not unnecessarily regenerate modules.builtin
headers_install: use local file handles
headers_check: fix perl warnings
export_report: fix perl warnings
...
sync_single_range_for_cpu and sync_single_range_for_device hooks in
swiotlb_dma_ops are unnecessary because sync_single_for_cpu and
sync_single_for_device are used there.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Becky Bruce <beckyb@kernel.crashing.org>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This adds support kexec on FSL-BookE where the MMU can not be simply
switched off. The code borrows the initial MMU-setup code to create the
identical mapping mapping. The only difference to the original boot code
is the size of the mapping(s) and the executeable address.
The kexec code maps the first 2 GiB of memory in 256 MiB steps. This
should work also on e500v1 boxes.
SMP support is still not available.
(Kumar: Added minor change to build to ifdef CONFIG_PPC_STD_MMU_64 some
code that was PPC64 specific)
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
This patch only moves the initial entry code which setups the mapping
from what ever to KERNELBASE into a seperate file. No code change has
been made here.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
During boot we change the mapping a few times until we have a "defined"
mapping. During this procedure a small 4KiB mapping is created and after
that one a 64MiB. Currently the offset of the 4KiB page in that we run
is zero because the complete startup up code is in first page which
starts at RPN zero.
If the code is recycled and moved to another location then its execution
will fail because the start address in 64 MiB mapping is computed
wrongly. It does not consider the offset to the page from the begin of
the memory.
This patch fixes this. Usually (system boot) r25 is zero so this does
not change anything unless the code is recycled.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Merging in current state of Linus' tree to deal with merge conflicts and
build failures in vio.c after merge.
Conflicts:
drivers/i2c/busses/i2c-cpm.c
drivers/i2c/busses/i2c-mpc.c
drivers/net/gianfar.c
Also fixed up one line in arch/powerpc/kernel/vio.c to use the
correct node pointer.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
.name, .match_table and .owner are duplicated in both of_platform_driver
and device_driver. This patch is a removes the extra copies from struct
of_platform_driver and converts all users to the device_driver members.
This patch is a pretty mechanical change. The usage model doesn't change
and if any drivers have been missed, or if anything has been fixed up
incorrectly, then it will fail with a compile time error, and the fixup
will be trivial. This patch looks big and scary because it touches so
many files, but it should be pretty safe.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Sean MacLennan <smaclennan@pikatech.com>
OF-style matching can be available to any device, on any type of bus.
This patch allows any driver to provide an OF match table when CONFIG_OF
is enabled so that drivers can be bound against devices described in
the device tree.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
By moving dma_mask into pdev_archdata, and adding archdata to
struct of_device, it makes it possible to substitute of_device
with struct platform_device, which is a stepping stone to
removing the of_platform bus entirely.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
* 'kvm-updates/2.6.35' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (269 commits)
KVM: x86: Add missing locking to arch specific vcpu ioctls
KVM: PPC: Add missing vcpu_load()/vcpu_put() in vcpu ioctls
KVM: MMU: Segregate shadow pages with different cr0.wp
KVM: x86: Check LMA bit before set_efer
KVM: Don't allow lmsw to clear cr0.pe
KVM: Add cpuid.txt file
KVM: x86: Tell the guest we'll warn it about tsc stability
x86, paravirt: don't compute pvclock adjustments if we trust the tsc
x86: KVM guest: Try using new kvm clock msrs
KVM: x86: export paravirtual cpuid flags in KVM_GET_SUPPORTED_CPUID
KVM: x86: add new KVMCLOCK cpuid feature
KVM: x86: change msr numbers for kvmclock
x86, paravirt: Add a global synchronization point for pvclock
x86, paravirt: Enable pvclock flags in vcpu_time_info structure
KVM: x86: Inject #GP with the right rip on efer writes
KVM: SVM: Don't allow nested guest to VMMCALL into host
KVM: x86: Fix exception reinjection forced to true
KVM: Fix wallclock version writing race
KVM: MMU: Don't read pdptrs with mmu spinlock held in mmu_alloc_roots
KVM: VMX: enable VMXON check with SMX enabled (Intel TXT)
...
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (92 commits)
powerpc: Remove unused 'protect4gb' boot parameter
powerpc: Build-in e1000e for pseries & ppc64_defconfig
powerpc/pseries: Make request_ras_irqs() available to other pseries code
powerpc/numa: Use ibm,architecture-vec-5 to detect form 1 affinity
powerpc/numa: Set a smaller value for RECLAIM_DISTANCE to enable zone reclaim
powerpc: Use smt_snooze_delay=-1 to always busy loop
powerpc: Remove check of ibm,smt-snooze-delay OF property
powerpc/kdump: Fix race in kdump shutdown
powerpc/kexec: Fix race in kexec shutdown
powerpc/kexec: Speedup kexec hash PTE tear down
powerpc/pseries: Add hcall to read 4 ptes at a time in real mode
powerpc: Use more accurate limit for first segment memory allocations
powerpc/kdump: Use chip->shutdown to disable IRQs
powerpc/kdump: CPUs assume the context of the oopsing CPU
powerpc/crashdump: Do not fail on NULL pointer dereferencing
powerpc/eeh: Fix oops when probing in early boot
powerpc/pci: Check devices status property when scanning OF tree
powerpc/vio: Switch VIO Bus PM to use generic helpers
powerpc: Avoid bad relocations in iSeries code
powerpc: Use common cpu_die (fixes SMP+SUSPEND build)
...
This is started as swsusp_32.S modifications, but the amount of #ifdefs
made the whole file horribly unreadable, so let's put the support into
its own separate file.
The code should be relatively easy to modify to support 44x BookEs as
well, but since I don't have any 44x to test, let's confine the code to
FSL BookE. (The only FSL-specific part so far is 'flush_dcache_L1'.)
Signed-off-by: Anton Vorontsov <avorontsov@mvista.com>
Acked-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Most of the MSCR bit assigments are different in e500mc versus
e500, and they are now write-one-to-clear.
Some e500mc machine check conditions are made recoverable (as long as
they aren't stuck on), most notably L1 instruction cache parity errors.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
'protect4gb' boot parameter was introduced to avoid allocating dma
space acrossing 4GB boundary in 2007 (the commit
569975591c).
In 2008, the IOMMU was fixed to use the boundary_mask parameter per
device properly. So 'protect4gb' workaround was removed (the
383af9525b). But somehow I messed the
'protect4gb' boot parameter that was used to enable the
workaround.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Right now if we want to busy loop and not give up any time to the hypervisor
we put a very large value into smt_snooze_delay. This is sometimes useful
when running a single partition and you want to avoid any latencies due
to the hypervisor or CPU power state transitions. While this works, it's a bit
ugly - how big a number is enough now we have NO_HZ and can be idle for a very
long time.
The patch below makes smt_snooze_delay signed, and a negative value means loop
forever:
echo -1 > /sys/devices/system/cpu/cpu0/smt_snooze_delay
This change shouldn't affect the existing userspace tools (eg ppc64_cpu), but
I'm cc-ing Nathan just to be sure.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
I'm not sure why we have code for parsing an ibm,smt-snooze-delay OF
property. Since we have a smt-snooze-delay= boot option and we can
also set it at runtime via sysfs, it should be safe to get rid of
this code.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When we are crashing, the crashing/primary CPU IPIs the secondaries to
turn off IRQs, go into real mode and wait in kexec_wait. While this
is happening, the primary tears down all the MMU maps. Unfortunately
the primary doesn't check to make sure the secondaries have entered
real mode before doing this.
On PHYP machines, the secondaries can take a long time shutting down
the IRQ controller as RTAS calls are need. These RTAS calls need to
be serialised which resilts in the secondaries contending in
lock_rtas() and hence taking a long time to shut down.
We've hit this on large POWER7 machines, where some secondaries are
still waiting in lock_rtas(), when the primary tears down the HPTEs.
This patch makes sure all secondaries are in real mode before the
primary tears down the MMU. It uses the new kexec_state entry in the
paca. It times out if the secondaries don't reach real mode after
10sec.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
In kexec_prepare_cpus, the primary CPU IPIs the secondary CPUs to
kexec_smp_down(). kexec_smp_down() calls kexec_smp_wait() which sets
the hw_cpu_id() to -1. The primary does this while leaving IRQs on
which means the primary can take a timer interrupt which can lead to
the IPIing one of the secondary CPUs (say, for a scheduler re-balance)
but since the secondary CPU now has a hw_cpu_id = -1, we IPI CPU
-1... Kaboom!
We are hitting this case regularly on POWER7 machines.
There is also a second race, where the primary will tear down the MMU
mappings before knowing the secondaries have entered real mode.
Also, the secondaries are clearing out any pending IPIs before
guaranteeing that no more will be received.
This changes kexec_prepare_cpus() so that we turn off IRQs in the
primary CPU much earlier. It adds a paca flag to say that the
secondaries have entered the kexec_smp_down() IPI and turned off IRQs,
rather than overloading hw_cpu_id with -1. This new paca flag is
again used to in indicate when the secondaries has entered real mode.
It also ensures that all CPUs have their IRQs off before we clear out
any pending IPI requests (in kexec_cpu_down()) to ensure there are no
trailing IPIs left unacknowledged.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Author: Milton Miller <miltonm@bga.com>
On large machines we are running out of room below 256MB. In some cases we
only need to ensure the allocation is in the first segment, which may be
256MB or 1TB.
Add slb0_limit and use it to specify the upper limit for the irqstack and
emergency stacks.
On a large ppc64 box, this fixes a panic at boot when the crashkernel=
option is specified (previously we would run out of memory below 256MB).
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
I saw this in a kdump kernel:
IOMMU table initialized, virtual merging enabled
Interrupt 155954 (real) is invalid, disabling it.
Interrupt 155953 (real) is invalid, disabling it.
ie we took some spurious interrupts. default_machine_crash_shutdown tries
to disable all interrupt sources but uses chip->disable which maps to
the default action of:
static void default_disable(unsigned int irq)
{
}
If we use chip->shutdown, then we actually mask the IRQ:
static void default_shutdown(unsigned int irq)
{
struct irq_desc *desc = irq_to_desc(irq);
desc->chip->mask(irq);
desc->status |= IRQ_MASKED;
}
Not sure why we don't implement a ->disable action for xics.c, or why
default_disable doesn't mask the interrupt.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We wrap the crash_shutdown_handles[] calls with longjmp/setjmp, so if any
of them fault we can recover. The problem is we add a hook to the debugger
fault handler hook which calls longjmp unconditionally.
This first part of kdump is run before we marshall the other CPUs, so there
is a very good chance some CPU on the box is going to page fault. And when
it does it hits the longjmp code and assumes the context of the oopsing CPU.
The machine gets very confused when it has 10 CPUs all with the same stack,
all thinking they have the same CPU id. I get even more confused trying
to debug it.
The patch below adds crash_shutdown_cpu and uses it to specify which cpu is
in the protected region. Since it can only be -1 or the oopsing CPU, we don't
need to use memory barriers since it is only valid on the local CPU - no other
CPU will ever see a value that matches it's local CPU id.
Eventually we should switch the order and marshall all CPUs before doing the
crash_shutdown_handles[] calls, but that is a bigger fix.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We ran into an issue where it looks like we're not properly ignoring a
pci device with a non-good status property when we walk the device tree
and instanciate the Linux side PCI devices.
However, the EEH init code does look for the property and disables EEH
on these devices. This leaves us in an inconsistent where we are poking
at a supposedly bad piece of hardware and RTAS will block our config
cycles because EEH isn't enabled anyway.
Signed-of-by: Sonny Rao <sonnyrao@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Switch to use the generic power management helpers.
Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Configuring a powerpc 32 bit kernel for both SMP and SUSPEND turns on
CPU_HOTPLUG to enable disable_nonboot_cpus to be called by the common
suspend code. Previously the definition of cpu_die for ppc32 was in
the powermac platform code, causing it to be undefined if that platform
as not selected.
arch/powerpc/kernel/built-in.o: In function 'cpu_idle':
arch/powerpc/kernel/idle.c:98: undefined reference to 'cpu_die'
Move the code from setup_64 to smp.c and rename the power mac
versions to their specific names.
Note that this does not setup the cpu_die pointers in either
smp_ops (request a given cpu die) or ppc_md (make this cpu die),
for other platforms but there are generic versions in smp.c.
Reported-by: Matt Sealey <matt@genesi-usa.com>
Reported-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Anton Vorontsov <avorontsov@mvista.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
There appear to be Pegasos systems which have the rtas-event-scan
RTAS tokens, but on which the event scan always fails. They also
have an event-scan-rate property containing 0, which means call
event scan 0 times per minute.
So interpret a scan rate of 0 to mean don't scan at all. This fixes
the problem on the Pegasos machines and makes sense as well.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
